1. Field of the Invention
The present invention relates to a liquid crystal display apparatus having a prism sheet arranged between a liquid crystal display device and a surface light source.
2. Description of the Related Art
A liquid crystal display apparatus in which a surface light source which emits illumination light toward a liquid crystal display device is arranged on an opposite side of an observation side of the liquid crystal display device is known from, e.g., Jpn. Pat. Appln. KOKAI Publication No. 2000-147429. In this liquid crystal display apparatus, a prism sheet is arranged between the surface light source and the liquid crystal display device to improve luminance of display. This prism sheet has a plurality of elongated prisms formed in parallel with each other, and condenses irradiation light from the surface light source by using the elongated prisms so that the light enters the liquid crystal display device.
Such a liquid crystal display apparatus has a problem that moire fringes which correspond to a difference between a prism pitch of the prism sheet and a pixel pitch of the liquid crystal display device and are caused due to an interference of light appear in an image displayed by light emitted from the surface light source and transmitted through the prism sheet and the liquid crystal display device to exit toward the observation side, thereby deteriorating a display quality.